[PATCH] libata: add pio flush for via atapi (was: Re: TR: ASUS A8V Deluxe, x86_64)

Backport the "pio flush" from the libata major update to 2.6.17 for via atapi.

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>